Retractable hydrofoil for marine vehicles

ABSTRACT

A marine vehicle with at least one hydrofoil at the lower hull of such marine vehicle, and at least one drive element for retracting a pair of hydrofoils mounted side-by-side on both sides of the symmetry axis of the hull of the marine vehicle. When hydrofoils are in the retracted position, the marine vehicle is converted to a conventional marine vehicle.

FIELD OF INVENTION

The present invention relates to a retractable hydrofoil arranged at the lower hull surface contacting the water of marine vehicles, such as yachts, boats.

BACKGROUND OF INVENTION

Hydrofoils are carriage wings provided at the lower hull of marine vehicles for carrying the hull over the water so as to prevent or minimize the water contact of the underwater hull surface, resulting in a reduction of drag forces originating from the craft's water contact thereby speeding up the craft, reducing fuel consumption, and providing stable travel

Conventionally, hydrofoils are statically mounted at the lower surface of hulls, meaning that hydrofoils can not be retracted that would convert such craft to a conventional craft having a flat hull i.e. without hydrofoils. The disadvantage of known marine vehicles therefore is the incapability of optionally effecting hydrofoils in a marine vehicle.

DESCRIPTION OF INVENTION

The object of the present invention is to provide retractable hydrofoils to marine vehicles so that the user of such vehicle can effect the hydrofoils as needed.

This object is achieved by a retractable hydrofoil mounted to the lower hull surface of a marine vehicle. Preferably, two hydrofoils, one to front part and one to rear part of the marine vehicle are mounted, and such retractable hydrofoils are driven by a drive mechanism for effecting the hydrofoils. When hydrofoils are in the retracted position, the marine vehicle is converted to a conventional marine vehicle

DESCRIPTION OF FIGURES

The present invention is to be evaluated together with annexed figures briefly described hereunder to make clear the subject embodiment and the advantages thereof

FIG. 1 illustrates hydrofoils mounted at the underwater hull of a marine vehicle.

FIG. 2 illustrates hydrofoil as situated on the front part of a marine vehicle's underwater hull

FIG. 3 illustrates hydrofoil as situated on the rear part of a marine vehicle's underwater hull.

REFERENCE NUMBERS OF PARTS IN FIGURES

1 Hull

2 Guide bar

3 Connecting bar

4 Hydrofoil

5 Housing

6 Piston

7 Sliding element

8 Sliding element

9 Joint

10 Hydrofoil wing

11 Housing channel

12 Joint

13 Piston

14 Sliding means

15 External surface of housing

DETAILED DESCRIPTION OF INVENTION

It should be noted that the terms “marine vehicle” and “craft” throughout this description mean any kind of marine vehicles such as boats, vessels, etc.

As seen in FIG. 1, the retractable hydrofoils according to a preferred embodiment of the present invention are situated at the front and rear parts of the craft's underwater hull. FIG. 2 gives a detail view of the hydrofoils situated at the front According to the preferred embodiment of the invention, the hydrofoils (4) are mounted in symmetrical pairs in both sides of a vertical symmetry axis. Such side-to-side situated hydrofoils (4) are connected to a sliding means (14) by means of joints (9), this connection enables the hydrofoils to rotate with respect to said sliding means (14). The sliding means (14) is guided by a guide bar (2) fixed to the lower part of hull in a vertically-extending manner and is capable to displace vertically along this guide bar (2).

On the upper surface of said hydrofoils (4) is formed a channel (10), wherein a sliding element (7) can linearly move in the lengthwise direction of said hydrofoils (4). Furthermore, a connecting bar (3) is pivotably coupled to said sliding element (7) by means of a joint, said bar (3) being actually in an upright position with respect to the ground when the hydrofoils (4) are in extended (open) position. Since the sliding element (7) is coupled to the channel (10) within the hydrofoil (4) by means of an engageable structure as well, it is capable of transferring force to the hydrofoil (4) in the vertical direction while the hydrofoil (4) is extended and retracted

The other end of the connecting bar (3) is connected pivotably to another sliding element (8) by means of another joint, this sliding element (8) being displaceable within a housing (5) The outer surface (15) of said housing (5) has the same surface form with the lower hull surface of the craft, when the hydrofoils are in retracted position. A channel (11) is formed within the housing (5), said sliding element (8) is able to move forward and backward in and along the channel (10).

According to the preferred embodiment of the present invention, a piston (6) is mounted in said housing channel (5) with one end of said piston (6) being connected to said sliding element (8); so, when the sliding element (8) is driven and hence the connecting bar (3) coupled to said element (8) is moved, the other sliding element (7) and thus the hydrofoil (4) connected to this sliding element (7) is brought into motion accordingly.

When the hydrofoils (4) are retracted, the underwater hull section is converted to a conventional form so that the lower surfaces of said hydrofoils (4), the outer surface of housing (15) catches surface form of the lower surface of the hull.

In an alternative embodiment of the present invention, there is also provided a piston (not illustrated in figures) extending in an axial direction in the channel (10) for driving the sliding elements (7) which displace in the hydrofoil channel (10)

FIG. 3 illustrates the subject hydrofoil as situated on the rear part of a marine vehicle's underwater hull. The working principle of the rear hydrofoil mechanism is basically identical to that of the front hydrofoil mechanism. The optional difference provided in the rear mechanism is that two connecting bars (3) are coupled to the sliding element (7) in the hydrofoil channel (10) by means of a joint (12), said bars (3) extending towards the terminating sections of the housing (5). Likewise, a sliding element (7) moving in said hydrofoil channel (10) can be driven in the lengthwise axis of the channel (10) by means of a piston (13) provided in the hydrofoil (4). 

1. A marine vehicle comprising at least one hydrofoil (4) at the lower hull (1) of such marine vehicle, characterized by comprising at least one drive element (6, 13) for retracting a pair of hydrofoils (4) mounted side-by-side on both sides of the symmetry axis of the hull (1) of the marine vehicle.
 2. A marine vehicle according to claim 1, characterized by comprising a guide bar (2) for guiding the pair of hydrofoils, which extends vertically with respect to the hull (1); at least one connecting bar (3) one end of which is connected to the hydrofoil (4) and the other end is connected to a housing into which said hydrofoil inserted while it is retracted
 3. A marine vehicle according to claim 2, characterized by comprising a sliding element (7) to which said connecting bar (3) is connected from one end, the sliding element (7) being displaceable in a channel (10) formed in the hydrofoil (4).
 4. A marine vehicle according to claim 2, characterized by comprising a sliding element (8) to which said connecting bar (3) is connected from the other end, the sliding element (8) being displaceable in a channel (11) formed in a housing (5).
 5. A marine vehicle according to claim 1, characterized in that the drive element (6) is a piston which drives the sliding element (8) displacing in the housing (5).
 6. A marine vehicle according to claim 1, characterized in that said drive element (6) is a piston which drives the sliding element (7) displacing in the hydrofoil (4)
 7. A marine vehicle according to claim 2, characterized by further comprising a sliding part (14) connected to the guide bar (2) so as to move along this bar (2).
 8. A marine vehicle according to claim 7, characterized by further comprising joints (9) providing rotatable connection of the hydrofoils (4) to the sliding part (14).
 9. A marine vehicle according to claim 1, characterized by comprising joints providing rotatable connection of the connecting bar (3) to the sliding elements (7, 8)
 10. A marine vehicle according to claim 1, characterized in that outer surface (15) of the housing (5) has the same surface form with the lower hull surface of the marine vehicle. 